Math210 Precalculus.

9. Without using technology, find the derivative of y = x cos(x) For this problem, use the method of Logarithmic Differentiation. 22 23 24 25 26 27 28 29 3 10. Jim uses fencing to create a large rectangle divided into three parts as shown in the diagram to ----length- the right (the black lines show where the fencing will be). width He wants to have a total area of 600 square feet and use the least amount of fencing possible. He also needs the length of the rectangle to be at most 100 feet long. Find the dimensions of the large rectangle so that the least amount of fencing is needed, 11. Use Calculus to find the inflection point(s) of the function y = 12 In(x) + x2 - 10x (note: only consider values where x > 0). Remember to justify your answer and/or show evidence for your answer. Note: a graph by itself is not sufficient justification for your answer. 12. Without using technology, find for the equation xe = sin(y?)